You just get 1 option to send an SMS when you can't take the call, and you want to set it busy with SMS. It is frustrating that only 1 SMS appears, and which is so difficult to edit and send in real time.

Now get a list of pre-defined messages instead of the just 1 option
Create your messages and send them when you are busy
You can edit the messages and write your own message
One Click access to send any SMS, and see your sent messages in History